UWA embryos could give birth to fail-safe shark repellent

By Simon White

The fish tank contains only 300 litres of water. The "sharks" inside it are still in the embryonic phase.

But here, at UWA's Oceans Institute, research is being undertaken that could help prove once and for all whether devices that emit electrical pulses really can consistently repel sharks.

Mr Kempster believes continued research can help hone devices already being used by divers and surfers in an attempt to ward off potentially deadly shark attacks.Credit:Ryan Kempster

PHD student Ryan Kempster's research into the impact of electrical pulses on bamboo shark embryos unearthed an amazing conclusion (and equally amazing vision - see below) when the foetus shut down its own heartbeat and "played dead".

The faint electrical pulse stimulated the signal that would be emitted by another animal, while the reaction of the embryo (bamboo sharks develop in an egg case outside their mother's body) was the equivalent of it trying to escape detection by a predator.

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Ryan Kempster's work with bamboo shark embryos could help perfect electrical sharp repellents used by divers and surfers.

Mr Kempster, 27, believes continued research can help hone devices already being used by divers and surfers in an attempt to ward off potentially deadly shark attacks.

"One of the question marks about the current electrical devices is about how you test them," Mr Kempster said.

"If you test them on wild animals, say a big shark, you might only get to test it once and then it goes away. You will know how it reacted one time, you won't necessarily know how it will react every time.

"The advantage we have with these embryos is that they can't move away. We can do the testing repeatedly.

"The natural reaction of sharks, when they first detect something they aren't familiar with - such as one of these electrical pulses - is to turn away. But we don't know yet whether that reaction stays the same for the fourth time or the fifth time."

The study has some fairly obvious commerical potential but Mr Kempster says he is a much better researcher than a businessman and intends to stick to the laboratory.

His sometimes jaw-dropping video, entitled Survival Of The Stillest, has been chosen for screening at the Beneath The Waves Festival in Virginia on the weekend.

Apart from the "playing dead" footage, it also contains eye-opening real-time vision of a bamboo shark being hatched.

Bamboo sharks are not native to WA waters and the ones currently involved in the research at the Oceans Institute have been flown in from Queensland.

But a breeding program is about to start which means Mr Kempster's future research "stars" will be home-grown.

There were three fatal shark attacks in WA in the second half of 2011, with debate ongoing about whether a "great white cull" was required.

Bodyboarder Kyle Burden was killed at Bunker Bay in the state's south-west in September, before two fatalities in October, when swimmer Bryn Martin disappeared off Cottesloe and Texan diver George Wainright was fatally mauled off Rottnest Island.